The planned parliamentary ratification of the Korea-U.S. free trade accord is set to put to test the solidarity of opposition groups, gauging how far they could go in forming an alliance to beat the ruling party in next year’s key elections, political observers note.

The Cabinet approved a new ratification bill for the trade agreement last Friday after fixing translation errors in its Korean text and submitted it to the National Assembly. In addition to the corrected text, the new ratification motion includes terms of a supplementary deal reached last December to reflect U.S. demands that South Korea ease its automotive and environmental standards.

The parliamentary committee on foreign affairs and trade retracted the previous bill, which had been submitted in October 2008, after a number of mistranslations were found in the Korean text last month.

The ruling Grand National Party is planning to pass the bill through the foreign affairs and trade panel within the ongoing extra session of the Assembly and then put it to a vote at a plenary session after the U.S. Congress ratifies it, probably before it goes into recess in August.

The four opposition parties have vowed to block the passage of the bill, asking for “renegotiation of the renegotiated deal,” which they say would bring more damage than benefits to the livelihoods of most Koreans. Rep. Kim Jin-pyo, floor leader of the main opposition Democratic Party, said early last week his party objected to the bill being sent to the parliament, claiming it failed to balance interests between South Korea and the U.S.

But three other smaller opposition parties are casting dubious eyes to whether the DP will put their words into action in blocking the passage of the Korea-U.S. trade deal. Their doubt came from the DP’s ambiguous stance on the Korea-EU free trade accord that the GNP had unilaterally passed on May 4.

The DP had agreed with the three other opposition groups to block the parliamentary passage of the trade deals with the EU and the U.S. as part of their joint policy agenda adopted ahead of the April 27 by-elections. But at the negotiating table days after the by-elections, then DP floor leader Park Jie-won gave consent to government and GNP officials on bipartisan approval of the Korea-EU trade pact.

Amid vehement protest from the smaller parties, the DP reversed the agreement with the ruling party and boycotted the parliamentary vote. DP Chairman Sohn Hak-kyu, who had remained ambiguous on the issue, made a last-minute decision to side with the splinter parties.

But the other groups hit the DP for discarding their earlier agreement on joint policy agenda, warning any move toward an opposition alliance would be derailed if the DP continued to behave in that way.

The dilemma for the DP is that while it should oppose the trade accord with the U.S. to strengthen the momentum for opposition solidarity, giving the impression of blind objection would make middle-class voters, who have become increasingly favorable to the DP, turn their backs on the party again. Sohn saw his approval rating, which rose above 15 percent shortly after the April by-elections, slide back to around 10 percent in the aftermath of his party’s flip-flopping over the Korea-EU trade pact.